It is becoming clear that inflammation lies at the root of multiple human diseases including cardiovascular disease, respiratory illness and cancer. The inflammatory process has been targeted on multiple fronts to alleviate its vast implications. Plant-derived triterpenoids are a class of 30-carbon molecules recently found to possess the ability to modulate the inflammatory response through a novel mechanism which results in the inhibited expression of key inflammatory enzymes. Triterpenoids are products of oxidosqualene cyclization and occur with diverse skeletal variety in the plant kingdom. The structural component contributing to triterpenoid anti-inflammatory activity has yet to be defined. A series of inflammatory cell assays, progressing from functional macrophages to primary mouse macrophages to knockout mouse macrophages, will be developed for systematic identification of potent triterpenoids, and elucidation of structural significance in this activity as well as mechanism of action. A stream-lined method, utilizing mass spectrometry and high performance liquid chromatography will be developed for obtaining triterpenoids from plant species known to synthesize unique skeletal variants of this class of plant metabolite. This same efficient procedure will be used for identifying and isolating novel triterpenoids present in plant species which exhibit anti-inflammatory properties. The panel of triterpenoids will be tested in the inflammatory models where structural and mechanistic insights may be distilled. This project endeavors to shed light upon the novel mechanism of anti-inflammatory activity exhibited by plant-derived triterpenoids by exploring the structural diversity of this class of metabolites and employing systematic biological assays for identifying potent candidates. Potentially, this research could yield new anti-inflammatories which could be obtained from a dietary source. Regardless, defining structural determinants of triterpenoid anti-inflammatory activity will be a novel contribution to this field.